## Limiting where a Turing Machine can write

Suppose I have a Turing Machine A, generated by somebody else, trying to break my system. To break my system they would have to write to the tape at some point X (this can be a range of the tape).

If I can force the machine A to be in some state q1 at some point, can I make a Turing Machine B such that for any Machine A it will never write in X?

## Custom Taxonomy is Missing (Or Limiting) Items

I created a custom taxonomy; "places" using toolset

region>country>city with 12 Regions / All Countries and just a few cities; 12 parents, 260 children

Where I am using the taxonomy in a post, custom post type or the menu, only some of the items show and it is quite random. 1/2 of Europe shows up 3 from the Caribbean, etc

I used the plugin Toolset; this issue has repeated in 4 different installs. I have worked with hosting and they assure me it is a development issue. I have worked with toolset and am on Day 6 of no solution; I have tried with different themes (Hello & Astra), Using Elementor or not (no plugins other than toolset itself; there is no support over the weekend. Does anyone have any idea WHY I would be missing just some of the taxonomy?

I am not seeing any errors in debugging

## Tech Casting – Limiting OP use with Modern Magic Ruleset

We’re many sessions into a homebrew cyberpunk 5E, and I’ve recently introduced hacking using this Modern Magic UA.

I can’t see in there any stipulation on how frequently a hacker class can cast a tech. Are there any hard and fast rules?

Context; my tech caster can load these hacks into a small portable ‘techdeck’ he carries around, and casts them from there. In last night’s session, he was able to basically run through an infiltration mission wildly casting Invisiblity to Cameras and Haywire on most challenges (it played out balanced enough in the end luckily, and didn’t ruin the story), but I’m just concerned it was a little OP.

So the question is… with Tech casting, is there a standardised limit I can impose on my players when they’re casting too many techs?

## Novice question: Limiting number of combo attempts with Fail2ban and 128 bits of entropy

Apps such as Fail2ban and DenyHosts enable unix administrators to limit username/password combo attempts to typically 3 attempts. But why 3? Some admins enable more, like 6 or 8 giving honest users a little more slack when making different attempts at a password they may not recall exactly. But why not 18? Or even 30?

If a sophisticated cracker wanted to brute force a combo with a scheme involving 128 bits of entropy, s/he would need to make trillions of attempts a second. So if an admin limited the total number of attempts to 100 using Fail2ban, wouldn’t the authentication system still be secure and robust, as long as the admin sets up their username/password scheme to require 128 bits of entropy?

## If I were to cast a spell limiting reactions (shocking grasp), does that mean the target can’t make a saving throw?

The shocking grasp cantrip states that the target can not take reactions until the start of its next turn. Therefore, the target should not be able to cast spells like absorb elements and shield. The second thing that I am unsure about is this: are saving throws reactions? If they are, someone could cast a spell using a saving throw against a target who can’t take reactions and theoretically they would automatically fail because of the inability to take a reaction. Through my knowledge, it never states anywhere that a saving throw takes a reaction, its just a roll.

Any rules that I should know about that would answer this question?

## Does limiting Sneak Attack to the Dexterity choice on Finesse Weapons imbalance anything?

Inspired by this question “Reckless Attack + Sneak Attack synergy?”.

This question brought my attention to something that seems odd. I was about to make a house ruling that in order to be able to utilize Sneak Attack that you had to choose the Dexterity option on the finesse weapon, this seems thematically sound as well as implied by the text in the ability. One of my players has tried to counter argue the point. Since I was not really convinced by his argument I thought I would ask the community.

Sneak Attack PHB 96 (emphasis mine):

Beginning at 1st level, you know how to strike subtly and exploit a foe’s distraction. Once per turn, you can deal an extra 1d6 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use a finesse or a ranged weapon.

Finesse weapons have the text as follows PHB 147 (emphasis mine):

When making an attack with a finesse weapon, you use your choice of your Strength or Dexterity modifier for the attack and damage rolls. You must use the same modifier for both rolls.

I understand that this would pidgeon-hole Rogues to be more Dexterity based but to be quite honest they already are quite reliant on it as most of their base kit and skills are leaning that direction. Most brute Rogues are multi-classed into a martial class in my experience as well. In addition classes are in and of themselves pidgeon-hole anyway.

To strike subtly implies to me more Dexterity rather than Strength.

So would making this change do anything imbalanced other than limiting arguably “sub-optimal” builds?

## Limiting Handbrake Using a Cgroup?

I’m following a tutorial for cgroups, but they don’t seem to be effective in limiting handbrake (A video conversion tool)’s performance.

I can’t really multi task while it is running.

I’ve installed cgroup* from apt and run the following commands to create the cgroup (Following this tutorial: https://www.devinhoward.ca/technology/2015/feb/implementing-cgroups-ubuntu-or-debian):

sudo cgcreate -a sarah -t sarah -g cpu:limitgroup echo 512 > cpu/limitgroup/cpu.shares cgexec -g cpu:limitgroup handbrake 

Handbrake still uses too much cpu though (I though the cgroup would limit it to 50%?):

How can I fix the situation and make handbrake use 50% CPU?

## Is Instagram limiting me?

Hi all! I've been using Instagram for a couple years now and I love the platform. I like the efficient, uncluttered presentation and its focus on imagery. I've built a following of just over 100 followers but lately I have noticed something strange. I have noticed a sharp decline in the engagement I'm getting. I used to easily get between 10-30 likes for a post but now I can hardly get 10…most days not even 5. This has been going on for a couple months now. I've been looking at the…

Is Instagram limiting me?

## Limiting property of polylogarithm ratio

I try (without success) to figure out what could be the following limit if any…
For real $$s$$ strictly $$> 1$$ and $$x \rightarrow +\infty$$ (x real) the limit of the polylogarithm ratio $$\frac{Li_{s-1}(x)}{Li_{s}(x)}$$